Adding upstream version 2.2.40.upstream/2.2.40upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 472 insertions, 0 deletions

diff --git a/common/openpgp-oid.c b/common/openpgp-oid.c
new file mode 100644
index 0000000..943fe3e
--- /dev/null
+++ b/common/openpgp-oid.c
@@ -0,0 +1,472 @@
+/* openpgp-oids.c - OID helper for OpenPGP
+ * Copyright (C) 2011 Free Software Foundation, Inc.
+ * Copyright (C) 2013 Werner Koch
+ *
+ * This file is part of GnuPG.
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of either
+ *
+ *   - the GNU Lesser General Public License as published by the Free
+ *     Software Foundation; either version 3 of the License, or (at
+ *     your option) any later version.
+ *
+ * or
+ *
+ *   - the GNU General Public License as published by the Free
+ *     Software Foundation; either version 2 of the License, or (at
+ *     your option) any later version.
+ *
+ * or both in parallel, as here.
+ *
+ * This file is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <ctype.h>
+#include <assert.h>
+
+#include "util.h"
+#include "openpgpdefs.h"
+
+/* A table with all our supported OpenPGP curves.  */
+static struct {
+  const char *name;   /* Standard name.  */
+  const char *oidstr; /* IETF formatted OID.  */
+  unsigned int nbits; /* Nominal bit length of the curve.  */
+  const char *alias;  /* NULL or alternative name of the curve.  */
+  int pubkey_algo;    /* Required OpenPGP algo or 0 for ECDSA/ECDH.  */
+} oidtable[] = {
+
+  { "Curve25519", "1.3.6.1.4.1.3029.1.5.1", 255, "cv25519", PUBKEY_ALGO_ECDH },
+  { "Ed25519",    "1.3.6.1.4.1.11591.15.1", 255, "ed25519", PUBKEY_ALGO_EDDSA },
+
+  { "NIST P-256",      "1.2.840.10045.3.1.7",    256, "nistp256" },
+  { "NIST P-384",      "1.3.132.0.34",           384, "nistp384" },
+  { "NIST P-521",      "1.3.132.0.35",           521, "nistp521" },
+
+  { "brainpoolP256r1", "1.3.36.3.3.2.8.1.1.7",   256 },
+  { "brainpoolP384r1", "1.3.36.3.3.2.8.1.1.11",  384 },
+  { "brainpoolP512r1", "1.3.36.3.3.2.8.1.1.13",  512 },
+
+  { "secp256k1",       "1.3.132.0.10",           256 },
+
+  { NULL, NULL, 0}
+};
+
+
+/* The OID for Curve Ed25519 in OpenPGP format.  */
+static const char oid_ed25519[] =
+  { 0x09, 0x2b, 0x06, 0x01, 0x04, 0x01, 0xda, 0x47, 0x0f, 0x01 };
+
+/* The OID for Curve25519 in OpenPGP format.  */
+static const char oid_cv25519[] =
+  { 0x0a, 0x2b, 0x06, 0x01, 0x04, 0x01, 0x97, 0x55, 0x01, 0x05, 0x01 };
+
+
+/* Helper for openpgp_oid_from_str.  */
+static size_t
+make_flagged_int (unsigned long value, char *buf, size_t buflen)
+{
+  int more = 0;
+  int shift;
+
+  /* fixme: figure out the number of bits in an ulong and start with
+     that value as shift (after making it a multiple of 7) a more
+     straigtforward implementation is to do it in reverse order using
+     a temporary buffer - saves a lot of compares */
+  for (more=0, shift=28; shift > 0; shift -= 7)
+    {
+      if (more || value >= (1<<shift))
+        {
+          buf[buflen++] = 0x80 | (value >> shift);
+          value -= (value >> shift) << shift;
+          more = 1;
+        }
+    }
+  buf[buflen++] = value;
+  return buflen;
+}
+
+
+/* Convert the OID given in dotted decimal form in STRING to an DER
+ * encoding and store it as an opaque value at R_MPI.  The format of
+ * the DER encoded is not a regular ASN.1 object but the modified
+ * format as used by OpenPGP for the ECC curve description.  On error
+ * the function returns and error code an NULL is stored at R_BUG.
+ * Note that scanning STRING stops at the first white space
+ * character.  */
+gpg_error_t
+openpgp_oid_from_str (const char *string, gcry_mpi_t *r_mpi)
+{
+  unsigned char *buf;
+  size_t buflen;
+  unsigned long val1, val;
+  const char *endp;
+  int arcno;
+
+  *r_mpi = NULL;
+
+  if (!string || !*string)
+    return gpg_error (GPG_ERR_INV_VALUE);
+
+  /* We can safely assume that the encoded OID is shorter than the string. */
+  buf = xtrymalloc (1 + strlen (string) + 2);
+  if (!buf)
+    return gpg_error_from_syserror ();
+  /* Save the first byte for the length.  */
+  buflen = 1;
+
+  val1 = 0; /* Avoid compiler warning.  */
+  arcno = 0;
+  do {
+    arcno++;
+    val = strtoul (string, (char**)&endp, 10);
+    if (!digitp (string) || !(*endp == '.' || !*endp))
+      {
+        xfree (buf);
+        return gpg_error (GPG_ERR_INV_OID_STRING);
+      }
+    if (*endp == '.')
+      string = endp+1;
+
+    if (arcno == 1)
+      {
+        if (val > 2)
+          break; /* Not allowed, error caught below.  */
+        val1 = val;
+      }
+    else if (arcno == 2)
+      { /* Need to combine the first two arcs in one octet.  */
+        if (val1 < 2)
+          {
+            if (val > 39)
+              {
+                xfree (buf);
+                return gpg_error (GPG_ERR_INV_OID_STRING);
+              }
+            buf[buflen++] = val1*40 + val;
+          }
+        else
+          {
+            val += 80;
+            buflen = make_flagged_int (val, buf, buflen);
+          }
+      }
+    else
+      {
+        buflen = make_flagged_int (val, buf, buflen);
+      }
+  } while (*endp == '.');
+
+  if (arcno == 1 || buflen < 2 || buflen > 254 )
+    { /* It is not possible to encode only the first arc.  */
+      xfree (buf);
+      return gpg_error (GPG_ERR_INV_OID_STRING);
+    }
+
+  *buf = buflen - 1;
+  *r_mpi = gcry_mpi_set_opaque (NULL, buf, buflen * 8);
+  if (!*r_mpi)
+    {
+      xfree (buf);
+      return gpg_error_from_syserror ();
+    }
+  return 0;
+}
+
+
+/* Return a malloced string representation of the OID in the buffer
+ * (BUF,LEN).  In case of an error NULL is returned and ERRNO is set.
+ * As per OpenPGP spec the first byte of the buffer is the length of
+ * the rest; the function performs a consistency check.  */
+char *
+openpgp_oidbuf_to_str (const unsigned char *buf, size_t len)
+{
+  char *string, *p;
+  int n = 0;
+  unsigned long val, valmask;
+
+  valmask = (unsigned long)0xfe << (8 * (sizeof (valmask) - 1));
+  /* The first bytes gives the length; check consistency.  */
+
+  if (!len || buf[0] != len -1)
+    {
+      gpg_err_set_errno (EINVAL);
+      return NULL;
+    }
+  /* Skip length byte.  */
+  len--;
+  buf++;
+
+  /* To calculate the length of the string we can safely assume an
+     upper limit of 3 decimal characters per byte.  Two extra bytes
+     account for the special first octect */
+  string = p = xtrymalloc (len*(1+3)+2+1);
+  if (!string)
+    return NULL;
+  if (!len)
+    {
+      *p = 0;
+      return string;
+    }
+
+  if (buf[0] < 40)
+    p += sprintf (p, "0.%d", buf[n]);
+  else if (buf[0] < 80)
+    p += sprintf (p, "1.%d", buf[n]-40);
+  else {
+    val = buf[n] & 0x7f;
+    while ( (buf[n]&0x80) && ++n < len )
+      {
+        if ( (val & valmask) )
+          goto badoid;  /* Overflow.  */
+        val <<= 7;
+        val |= buf[n] & 0x7f;
+      }
+    if (val < 80)
+      goto badoid;
+    val -= 80;
+    sprintf (p, "2.%lu", val);
+    p += strlen (p);
+  }
+  for (n++; n < len; n++)
+    {
+      val = buf[n] & 0x7f;
+      while ( (buf[n]&0x80) && ++n < len )
+        {
+          if ( (val & valmask) )
+            goto badoid;  /* Overflow.  */
+          val <<= 7;
+          val |= buf[n] & 0x7f;
+        }
+      sprintf (p, ".%lu", val);
+      p += strlen (p);
+    }
+
+  *p = 0;
+  return string;
+
+ badoid:
+  /* Return a special OID (gnu.gnupg.badoid) to indicate the error
+     case.  The OID is broken and thus we return one which can't do
+     any harm.  Formally this does not need to be a bad OID but an OID
+     with an arc that can't be represented in a 32 bit word is more
+     than likely corrupt.  */
+  xfree (string);
+  return xtrystrdup ("1.3.6.1.4.1.11591.2.12242973");
+}
+
+
+/* Return a malloced string representation of the OID in the opaque
+ * MPI A.  In case of an error NULL is returned and ERRNO is set.  */
+char *
+openpgp_oid_to_str (gcry_mpi_t a)
+{
+  const unsigned char *buf;
+  unsigned int lengthi;
+
+  if (!a
+      || !gcry_mpi_get_flag (a, GCRYMPI_FLAG_OPAQUE)
+      || !(buf = gcry_mpi_get_opaque (a, &lengthi)))
+    {
+      gpg_err_set_errno (EINVAL);
+      return NULL;
+    }
+
+  buf = gcry_mpi_get_opaque (a, &lengthi);
+  return openpgp_oidbuf_to_str (buf, (lengthi+7)/8);
+}
+
+
+/* Return true if (BUF,LEN) represents the OID for Ed25519.  */
+int
+openpgp_oidbuf_is_ed25519 (const void *buf, size_t len)
+{
+  return (buf && len == DIM (oid_ed25519)
+          && !memcmp (buf, oid_ed25519, DIM (oid_ed25519)));
+}
+
+
+/* Return true if A represents the OID for Ed25519.  */
+int
+openpgp_oid_is_ed25519 (gcry_mpi_t a)
+{
+  const unsigned char *buf;
+  unsigned int nbits;
+
+  if (!a || !gcry_mpi_get_flag (a, GCRYMPI_FLAG_OPAQUE))
+    return 0;
+
+  buf = gcry_mpi_get_opaque (a, &nbits);
+  return openpgp_oidbuf_is_ed25519 (buf, (nbits+7)/8);
+}
+
+
+/* Return true if (BUF,LEN) represents the OID for Curve25519.  */
+int
+openpgp_oidbuf_is_cv25519 (const void *buf, size_t len)
+{
+  return (buf && len == DIM (oid_cv25519)
+          && !memcmp (buf, oid_cv25519, DIM (oid_cv25519)));
+}
+
+
+/* Return true if the MPI A represents the OID for Curve25519.  */
+int
+openpgp_oid_is_cv25519 (gcry_mpi_t a)
+{
+  const unsigned char *buf;
+  unsigned int nbits;
+
+  if (!a || !gcry_mpi_get_flag (a, GCRYMPI_FLAG_OPAQUE))
+    return 0;
+
+  buf = gcry_mpi_get_opaque (a, &nbits);
+  return openpgp_oidbuf_is_cv25519 (buf, (nbits+7)/8);
+}
+
+
+/* Map the Libgcrypt ECC curve NAME to an OID.  If R_NBITS is not NULL
+   store the bit size of the curve there.  Returns NULL for unknown
+   curve names.  If R_ALGO is not NULL and a specific ECC algorithm is
+   required for this curve its OpenPGP algorithm number is stored
+   there; otherwise 0 is stored which indicates that ECDSA or ECDH can
+   be used. */
+const char *
+openpgp_curve_to_oid (const char *name, unsigned int *r_nbits, int *r_algo)
+{
+  int i;
+  unsigned int nbits = 0;
+  const char *oidstr = NULL;
+  int algo = 0;
+
+  if (name)
+    {
+      for (i=0; oidtable[i].name; i++)
+        if (!strcmp (oidtable[i].name, name)
+            || (oidtable[i].alias && !strcmp (oidtable[i].alias, name)))
+          {
+            oidstr = oidtable[i].oidstr;
+            nbits  = oidtable[i].nbits;
+            algo   = oidtable[i].pubkey_algo;
+            break;
+          }
+      if (!oidtable[i].name)
+        {
+          /* If not found assume the input is already an OID and check
+             whether we support it.  */
+          for (i=0; oidtable[i].name; i++)
+            if (!strcmp (name, oidtable[i].oidstr))
+              {
+                oidstr = oidtable[i].oidstr;
+                nbits  = oidtable[i].nbits;
+                algo   = oidtable[i].pubkey_algo;
+                break;
+              }
+        }
+    }
+
+  if (r_nbits)
+    *r_nbits = nbits;
+  if (r_algo)
+    *r_algo = algo;
+  return oidstr;
+}
+
+
+/* Map an OpenPGP OID to the Libgcrypt curve NAME.  Returns NULL for
+   unknown curve names.  Unless CANON is set we prefer an alias name
+   here which is more suitable for printing.  */
+const char *
+openpgp_oid_to_curve (const char *oidstr, int canon)
+{
+  int i;
+
+  if (!oidstr)
+    return NULL;
+
+  for (i=0; oidtable[i].name; i++)
+    if (!strcmp (oidtable[i].oidstr, oidstr))
+      return !canon && oidtable[i].alias? oidtable[i].alias : oidtable[i].name;
+
+  return NULL;
+}
+
+
+/* Return true if the curve with NAME is supported.  */
+static int
+curve_supported_p (const char *name)
+{
+  int result = 0;
+  gcry_sexp_t keyparms;
+
+  if (!gcry_sexp_build (&keyparms, NULL, "(public-key(ecc(curve %s)))", name))
+    {
+      result = !!gcry_pk_get_curve (keyparms, 0, NULL);
+      gcry_sexp_release (keyparms);
+    }
+  return result;
+}
+
+
+/* Enumerate available and supported OpenPGP curves.  The caller needs
+   to set the integer variable at ITERP to zero and keep on calling
+   this function until NULL is returned.  */
+const char *
+openpgp_enum_curves (int *iterp)
+{
+  int idx = *iterp;
+
+  while (idx >= 0 && idx < DIM (oidtable) && oidtable[idx].name)
+    {
+      if (curve_supported_p (oidtable[idx].name))
+        {
+          *iterp = idx + 1;
+          return oidtable[idx].alias? oidtable[idx].alias : oidtable[idx].name;
+        }
+      idx++;
+    }
+  *iterp = idx;
+  return NULL;
+}
+
+
+/* Return the Libgcrypt name for the gpg curve NAME if supported.  If
+ * R_ALGO is not NULL the required OpenPGP public key algo or 0 is
+ * stored at that address.  If R_NBITS is not NULL the nominal bitsize
+ * of the curves is stored there.  NULL is returned if the curve is
+ * not supported. */
+const char *
+openpgp_is_curve_supported (const char *name, int *r_algo,
+                            unsigned int *r_nbits)
+{
+  int idx;
+
+  if (r_algo)
+    *r_algo = 0;
+  if (r_nbits)
+    *r_nbits = 0;
+  for (idx = 0; idx < DIM (oidtable) && oidtable[idx].name; idx++)
+    {
+      if ((!strcmp (name, oidtable[idx].name)
+           || (oidtable[idx].alias && !strcmp (name, (oidtable[idx].alias))))
+          && curve_supported_p (oidtable[idx].name))
+        {
+          if (r_algo)
+            *r_algo = oidtable[idx].pubkey_algo;
+          if (r_nbits)
+            *r_nbits = oidtable[idx].nbits;
+          return oidtable[idx].name;
+        }
+    }
+  return NULL;
+}